Biopsy is the removal and study of body tissue from a body for medical diagnosis, research or for other purposes. For example, clinicians frequently remove biopsy samples from patients to screen for the existence of a disease condition, such as cancer, and to determine the extent to which the disease condition has spread throughout the body. The art provides various biopsy instruments useful in acquiring tissue samples from different areas of the body.
Currently available biopsy instruments typically comprise a two-part needle assembly in which a cutting cannula surrounds a stylet that defines a specimen notch. In use, a spring mechanism initially advances the stylet into a target tissue to force a core tissue sample into the specimen notch, and then advances the cannula over the specimen notch to separate the core sample from the surrounding tissue. The user then removes the biopsy instrument and the core sample it contains from the body. An example of this type of instrument is described in U.S. Pat. No. 5,538,010 to Darr et al. for a BIOPSY NEEDLE ASSEMBLY DEVICE, the entire disclosure of which is incorporated herein by reference.
Another exemplary biopsy instrument is the QUICK-CORE® Biopsy Needle assembly available from Cook Incorporated. In this instrument, each of the stylet and the cannula defines a series of notches that impart flexibility onto the instrument, facilitating its navigation through tortuous anatomy. This instrument is described and illustrated in Unites States Patent Application Publication No. 2004/0133124 to Bates et al. for a FLEXIBLE BIOPSY NEEDLE ASSEMBLY.
Several currently available soft tissue biopsy needle assemblies utilize an in-line-type handle on the proximal end of the device for the main body of the instrument. These handles offer limited control over inserting and guiding the biopsy needle assembly into the patient because they force the user to arrange their hand that holds the instrument into an open palm, supine position. This position can be uncomfortable and can even place a strain on the user's hand(s), finger(s), and/or wrist. Furthermore, these handles also can force the user to contract their index and/or middle finger as they use their other hand to advance the needle assembly tip into the biopsy area. This unintended finger contraction can move the biopsy needle assembly out of alignment with the biopsy area, which may result in the core sample being removed from tissue that is spaced from the target tissue.